The evidence in these data suggests that the difference in average pain intensity after FIB versus SB was not significant (95% confidence interval, -2.2-1.4 NRS units).

Nerve injury after peripheral nerve blockade (PNB) is a potentially devastating complication that can result in permanent disability. 1 Data from a recent review of published studies suggest that the incidence of neuropathy after PNB varies depending on the anatomical location, ranging from 0.03% for supraclavicular blocks to 0.3% for femoral blocks to up to 3% for interscalene blocks. 2 Fortunately, the vast majority of these neuropathies seem to be temporary and resolve over weeks to months. However, the etiology of neurologic injury related to PNB remains unclear. Suggested etiologies include mechanical trauma from the needle, nerve edema and/or hematoma, pressure effects of the local anesthetic injectate, and neurotoxicity of the injected compounds, both local anesthetics and adjuvants (eg, epinephrine). 3 Confounding factors that may play a role in nerve injury include preexisting neuropathies (eg, diabetes mellitus), surgical manipulation, prolonged tourniquet pressure or compression from postoperative casting. 4 It is well established that direct injection into peripheral nerves (eg, accidentally during intramuscular administration) can result in nerve injury. 5 As a result, regional anesthesiologists have traditionally adopted the stance that intraneural injection of local anesthetic solutions results in nerve injury after PNB. This stance has recently been challenged by several controversial studies that suggest that the relationship between